I am curious if you have an overriding need to have data originating from NMEA-2000 devices about

--heading--wind--depth--speed--temperature, and--log

translated to NMEA-0183 and then repeated on USB and WiFi. What devices are you planning to interconnect and how will you use that data? Is this for your Outrage 17 boat? What NMEA-2000 sensors do you have now?

peteinsf

posted 06-03-2015 04:18 PM ET (US)
True, not that useful for an Outrage but for the Challenger maybe. I was looking for a tablet or Toughbook for chart plotting, the display of AIS ship tracks and any DCS alarms. Some of the systems have the option of adding NEMA2000 sourced data to the single screen.

Hulls speed, depth, wind and all the engine parameters can be added to the edges of the map and alarms can be configured.

jimh

posted 06-04-2015 08:18 AM ET (US)
I don't see engine parameters in the list of data to be translated and carried to WiFi by the Vespermarine device. Can you give more information on the WiFi display device that will be showing your engine parameters that originated from NMEA-2000?

The NMEA-2000 protocol does not provide for WiFi transport, as far as I know. What sort of tablet will you use? What operating system? And what application will you be running to see the engine parameters? And how will the engine parameters be carried to the tablet via WiFi? Have you tested all of this with the Vespermarine device?

Before embarking on this project, I suggest you contact Vespermarine to confirm that their device has the capabilities you ascribed to it.

Hoosier

posted 06-04-2015 08:51 AM ET (US)
Pete, you said this "the display of AIS ship tracks", do you only want to display tracks or also send AIS data? There are many options out there to receive and display AIS stuff, my Link 8 radio does it on my HDS.

jimh

posted 06-04-2015 02:04 PM ET (US)
I must also caution about the expectation that the historical tracks of AIS target vessels will be displayed by a chart plotter. I have investigated how two types of chart plotters will display AIS target vessel information. What I have found is that the displays are likely to show predicted courses for the AIS target, based on the AIS target's reported speed, course, and heading information that is sent in the AIS transmission. But I have not seen a chart plotter that accumulates the historical positions of AIS targets and then displays the historical positions of those targets as a track line on the display.

If you have a chart plotter in mind that has that feature, please mention the manufacturer and the model. I would like to see how that presentation is done.

The AIS system was designed as a collision avoidance system, and, considering that function, it makes very good sense that an AIS display would show the future position of a vessel. Seeing the future position of a vessel on a chart display gives much more information about the possibility of a collision in the future than could be obtained by seeing a plot of the historical positions of the AIS target. It also seems reasonable that presenting both an historical track and a predicted track might be confusing.

For some examples of a chart display on two different types of chart plotter than show predicted tracks in the future for AIS targets, see the illustrations included with my article at

It is fairly simple for a display to show the present position of an AIS target and to predict its future position because all of the data necessary to compute those positions is transmitted by the AIS target with every transmission. On the other hand, for a display to be able to show historical tracks of AIS targets, the display device or some auxiliary device must collect and archive a great deal of prior transmissions from the AIS target. The display would then need have some sort of drawing routine that allowed it to draw the archived positions and connect them with lines, drawing this onto the chart in some sort of manner that would provide a clear presentation.

Some websites and their website developers, such as MARINETRAFFIC.COM, have apparently developed such software and can show historical tracks of vessels as an option. Whether or not this same presentation can be obtained from a typical marine chart plotter seems less likely, to me.